a problem of sticks

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        int n;
        cin>>n;
        set <int>s;
        for(int i=0;i<n;i++)
           {
               int c;cin>>c;
               if(c!=0)
               s.insert(c);
           }
           cout<<s.size()<<endl;

    }

}